What was the anti-Stalin book Ayatollah Khamenei commented on?

The book “Children of the Arbat” by Anatoly Rybakov is an anti-Stalin novel. [According to the writer] It can be said that Stalin, who gained experience studying in a religious school or an orthodox Christian school, was rhetorically gifted at speaking to the people.

October 20, 1991

During certain eras such as the Stalin era, power was in the hands of only one person. However, later on the central board of the communist party had control over everything in the country. A lot of pressure was exerted on the people. Many limitations were imposed. The people went through a lot of hardships. During those times, certain writings used to leak out of Russian borders. Some of these writings used to be translated into Farsi and I used to read them. Before the collapse of the Soviet Union many of these bitter and unpleasant dimensions were kept hidden. It was only after the collapse of the Soviet Union that many things became clear: what they had been doing and what limitations they had imposed on the people. The literary works of the time show the hardships that the people of Russia went through during the rule of the Soviet Union. That is to say, the revolution was totally derailed from the beginning. The revolution did not just fail to continue. No, the original promises were not fulfilled at all.